Gardeners' Notes:

15 years ago, I bought a Persicaria bistorta recommended by a local nursery in Anchorage, Alaska. We innocently planted it near a pond as suggested by nursery owner. At first we saw it as a pretty pink spring flower that bloomed at the same time as our purple irises - a nice combination. Then we realized it's the devil and incredibly invasive. We've tried many times to remove it and it always comes back stronger than ever. It's seemingly impossible to eradicate and has made gardening around the pond completely intolerable. We've lost so many valuable plants to its relentless spread. I've finally given up - it's relentless and we're old.

The May/June flowers are beautiful, and this is one of the plants that most frequently elicits questions from those on garden tours. It's not commonly grown in New England. It blooms for about 3 weeks in May/June. Deadheading results in some scattered rebloom.

In North America, the plants in cultivation are the cultivar 'Superba', which has fatter, showier flower spikes and is shown in most of the above photos. I have grown it for 15 years and never seen a seedling.

Armitage (_Herbaceous Perennial Plants_) states that it's hardy in Z3-7, and that it does poorly in the hot humid summers of the southeastern US.

It's an aggressive spreader in the garden by a thick shallow rhizome. A garden thug, it's not difficult to control if you're willing to di... read moreg out the excess annually. But I now regret not planting it in a sunken bottomless container, as I wasn't vigilant enough to stop it from bulldozing its way over some smaller neighbors and killing them.

Fortunately, I haven't seen this self-sow. It isn't ecologically invasive in New England. BONAP says it's naturalized in only 3 states, and is nowhere invasive of natural habitat.

It is native to Europe and northern and western Asia. It isn't listed in the flora of North America.

In the heat of summer, it does require a bit more water than most of my perennials, but it isn't the thirstiest, either. It probably helps that the soil is a heavy silt, and it gets dappled shade most of the day. Tolerates boggy soil, and is suitable for water gardens. The foliage is deciduous here, not evergreen.

I actually have this plant growing under a red maple(see picture). I do water it often as it likes moisture. But, if some say it may become an invasive plant in optimum conditions then it will hopefully control itself in dry shade. It took a while to get it established under this tree but supply it with plenty of organic matter and mulch and it makes a fine show in May/June. Becoming more available in U.S...more common in England.

A semi-evergreen perennial from Europe and parts of Asia, naturalised elsewhere in the Northern Hemisphere.

Has mid-green, veined, ovate, basal leaves which become smaller and more triangular as they appear up the stems. Bears dense spikes of small, pink, sometimes white flowers which bees love.

Flowers May-September

Likes a moist but well drained soil in sun or partial shade. It will tolerate drier soils but will not flower nearly so well.

It was once used as an antidote to poisons and for treatment of jaundice, stomach ulcers, dysentry, cholera, measles and a number of other diseases (and yes you guessed it, a cure for the plague). It was also considered a useful midwifery herb.

It's been used as a mouthwash for g... read moreum ulcers and toothache; in preparations to treat acne and insect bites and to staunch the blood from small wounds, the plant does have astringent properties.

It was also once used in leather tanning.

Suprisingly it's leaves are edible and has long been used in the north of England in a pudding of various other leaves. It's still occasionally eaten today as a steamed vegetable with lamb or pork.